IAD to BUF flight delays & on-time performance
Nonstop flights from Washington Dulles International Airport to Buffalo Niagara International Airport · 283 miles · Aug 2025 – Jul 2026
No FAA-reported ground stops or delays at IAD or BUF right now. Individual flights can still be delayed by the airline; check with your airline for your flight.
Key facts
- Flights from Washington (IAD) to Buffalo (BUF) arrived on time 85% of the time in Aug 2025 – Jul 2026, better than the 78% national average.
- 4.8% were cancelled, and 8% arrived an hour or more late.
- Departures scheduled around 8am did best (94% on time); around 5pm did worst (78%).
- Tuesday was the most reliable day to fly (91% on time) and Wednesday the least (80%).
- The largest source of delay minutes was extreme weather (41%).
Which airline is most on time from IAD to BUF?
Ranked by on-time arrival rate. Regional airlines fly under their partner's brand (e.g. SkyWest for Delta Connection or United Express).
| Airline | On time | Cancelled | Avg delay | 1 hr+ late | Flights |
|---|---|---|---|---|---|
| United Airlines | 100% | 0.0% | 3 min | 0.0% | 5 |
| Republic AirwaysRegional airline operating flights for American Eagle, Delta Connection and United Express. | 84% | 4.9% | 16 min | 8.1% | 142 |
Best time of day to fly
On-time arrival rate by scheduled departure hour (local time).
- 8am94%52 flights
- 5pm78%27 flights
- 10pm81%63 flights
Best day of the week
On-time arrival rate by day of departure.
- Monday80%4.8% cancelled
- Tuesday91%15.4% cancelled
- Wednesday80%4.8% cancelled
- Thursday88%3.7% cancelled
- Friday87%0.0% cancelled
- Saturday89%5.0% cancelled
- Sunday81%4.5% cancelled
On-time trend by month
Why flights are late
Share of delay minutes by cause, as reported by airlines to the DOT.
- Extreme weather41%
- Airline (crew, maintenance, cleaning, fueling)23%
- Late-arriving aircraft19%
- Air traffic control & airport congestion16%
- Security0%
Why flights are cancelled
Share of cancellations by reason.
- Air traffic control & airport congestion57%
- Extreme weather29%
- Airline (crew, maintenance, cleaning, fueling)14%
- Security0%
IAD to BUF: common questions
- How often are IAD to BUF flights on time?
- 85% of flights arrived less than 15 minutes late in Aug 2025 – Jul 2026, compared with 78% for all US flights.
- How often are flights from Washington to Buffalo cancelled?
- 4.8% of scheduled flights were cancelled (7 of 147).
- How long are typical delays?
- Across all flights the average arrival delay was 16 min (early arrivals count as zero). Flights that were late arrived 98 min behind schedule on average, and 7.9% of flights were an hour or more late.
- How long is taxi time at IAD?
- Flights on this route spent 22 min taxiing from the gate to takeoff on average.
Related routes
Return trip: BUF to IAD — 88% on time
More flights from Washington
Data: U.S. DOT Bureau of Transportation Statistics, Aug 2025 – Jul 2026 (12 months). Latest month published by BTS: July 2026. Route: IAD → BUF, nonstop flights by US airlines that report to the DOT. How we calculate this.